Given standard reduction potentials E°(Zn2+/Zn) = -0.76 V and E°(Cu2+/Cu) = +0.34 V, what is the standard electromotive force (E°cell) of the Daniell cell?
Answer and explanation
Correct answer: A. +1.10 V
E°cell = E°cathode (reduction) - E°anode (oxidation) = (+0.34 V) - (-0.76 V) = +1.10 V. The positive cell potential indicates that the reaction Zn + Cu2+ -> Zn2+ + Cu is spontaneous under standard conditions.
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